cosmom3- Sorry, got caught up in the off-topic comments. You're right, I'll go delete the offending post. Threads sometimes go off-topic here, not that that's any excuse. I really didn't mean it to sound the way it came across (Accumulator removes foot from mouth).
Those scratches look pretty severe for the PC, but if you get something aggressive *but still PC-friendly* you might get 'em knocked down to where the owner will be OK with hem. At least they'll be less noticeable and that might be just fine for a track car. I'd try something more aggressive than the Scratch-X (which you'll probably find handy to have around anyhow).
1Z Ultra followed by their Paint Polish work well by hand/PC, but you'd have to order them. I'd probably try 3M PI-III RC (05937) with a 4" pad myself, following with PI-III MG (05937). I know, I keep recommending those and saying how they're out of production, but I know there're still bottles out there; my local autobody/paint supply place has them on the shelf.
Again, sorry about the earlier post; as you said, that wasn't the topic of the thread and as I said, I wasn't there. Sounds like a well set-up car for the purpose and like the owner knows what he wants to do with it and how.